Chemokines are proinflammatory cytokines that are chemoattractants and activators of specific types of leukocytes. Members of this family share common structural motifs, in particular the positions of four cysteines, as well as other highly conserved regions of primary structure. Despite their similarities, most chemokines have non-overlapping target cell specificities. Chemokines can be grouped into two subfamilies, chemokine-.alpha. and chemokine-.beta.proteins, based on structural and genetic criteria.
Monocyte chemoattractant protein-1 (MCP-1) is a member of the chemokine-.beta. family of proinflammatory cytokines. The amino acid sequence of human MCP-1 is disclosed in Rollins, Molecular and Cellular Biology, Vol. 9, No. 11, pp. 4687-4695, Nov. 1989. MCP-1 attracts and activates monocytes, to the exclusion of neutrophils, at subnanomolar concentrations. MCP-1 is structurally and genetically related to interleukin-8 (IL-8), a neutrophil-specific chemo-attractant, which is member of the chemokine-.alpha. family.
Monocytes are attracted to damaged coronary arteries, such as the damage caused by coronary artery angioplasty, and are involved in causing restenosis.